Bit mounting means for boring



Aug. 11, 1959 A. RJBIEDESS 2,899,187

BIT MOUNTING MEANS FOR BORING HEAD CUTTERS Filed Dec. 16; 1957 IN V EN TOR.

A TTORNE V Anthony: R Biedess BIT MOUNTING MEANS FOR BORING HEAD CUTTERS Anthony R. Biedess, Chicago, 111., assignor to Goodman Manufacturing Company, Chicago, Ill., a corporation of Illinois Application December 16, 1957, Serial No. 703,117 4 Claims. (Cl. 262-33) This invention relates to improvements in cutters and more particularly relates to cutters of the rotary type particularly adapted for continuous mining machines and the like.

A principal object of the invention is to provide a new and improved rotary cutter and bit mounting means therefore in which the bit mounting means may readily be arranged to fit the different cutting radii of the various cutters.

A further object of the invention is to provide a rotary cutter and bit mounting means therefore in which individual mounting blocks are provided for each cutter and in which the blocks and mounting means therefore are so arranged as to enable the bits to readily be positioned to fit different cutting radii and to be readily arranged in different bit patterns to suit various cutting conditions.

A further object of the invention is to provide a simplified and improved means for detachably mounting cutter bits on the arcuate face of a rotary cutter of a continuous mining machine and the like, in which individual mounting blocks are provided for each bit, each having ans Pat an open bit receiving recesses therein closed by abutting engagement of the blocks with respect to each other, and in which the blocks have non-parallel forward and rear faces to enable the blocks to readily conform to a required cutting radius, for making an annular kerf in a coal face.

These and other objects of the invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawings wherein:

Figure l is a fragmentary front view of a radial cutter arm of a boring head for a continuous mining machine, illustrating one form in which my invention may be embodied; and

Figure 2 is a fragmentary plan view of the radial cutter and the bit mounting blocks mounted thereon looking in the direction of the arrows 22 of Figure 1, with certain parts broken away and certain other parts shown in section.

In the embodiment of the invention illustrated in the drawing, reference numeral 20 generally designates a rotatable boring head of a boring type of continuous mining machine. The boring head 20 may be a well known form commonly used in boring types of continuous mining machines making boring cuts in a coal face upon rotatable movement of the boring head as it is axially fed into the coal face, so need only herein be shown and described in sufficient detail to render the present invention readily understandable. The boring head 20 includes a radial arm 21 extending radially from a central hub (not shown) and having a segmental cutter 21c spaced radially outwardly from the hub of the boring head and a second segmental cutter 25c spaced radially outwardly of the cutter 21c.

The segmental cutters 21c and 25c are of a similar construction and each have a series of individual bit 2,899,187. Patented Aug. 11, 1959 mounting blocks 53 mounted thereon, angularly arranged with respect to each other to conform to the radial spacings of the cutters from the axis of rotation of the arm 21, so only one of said cutters need herein be shown and described in detail.

The bit mounting blocks 53 are shown in Figure 2 as being arranged in tiers with the trailing tier of bits spaced in advance of the leading tiers as in an application Serial No. 703,078 filed herewith by John S. Newton and Cedric E. McWhorter, owned by the assignee of this application and entitled Cutting Device for Coal and the Like. It should, therefore, be understood that the tiered arrangement of the bits is no part of my present invention, and that the bits may be arranged in tiered relation with respect to each other or at the same cutting gage, if desired.

Referring now in particular to Figure 2, each mounting block 53 forms a mounting for a cutter bit 55 and is suitably mounted on an advance segmental face 54 of the cutter 25c to position the bits to cut an annular kerf conforming to the arc of the advance face 54, determined by the radial spacing of said advance face from the center of rotation of the arm 21.

Each bit 55 is shown as having a rectangular shank 56 having a tapered rear side 57. The shank 56 is insertable within an open socket 59 opening to the advance face of the block 53 and having parallel side walls and a tapered rear Wall 60 conforming to the taper of the tapered rear side 57 of the shank 56. The inner side of each block is slotted in intersecting relation with respect to the open socket 59 to provide openings 61 in the individual blocks 53, to afford access to the inner ends of the shanks 56, to enable the bits to be removed by a pry bar or the like.

The shank 56 terminates at its outer end into an enlarged head 62 having a hardened cutter tip 63 bonded to the advance or forward face thereof. The cutter tip 63 is shown as being recessed within the advance face of the head 62 and may be made from an abrasive resistant hardened cutting material, such as a tungsten carbide.

The sockets 59 are pitched at varying angles with respect to each other and to an arc struck from the axis of rotation of the cutter and extending along the center line thereof, to position the bits to cut clearance for the cutter. As shown in Figure l, certain sockets extend at right angles to the arcuate center line of the cutter, while certain other sockets are inclined upwardly and downwardly with respect to said center line to cut clearance for the cutter and the blocks 53.

Each block 53 has non-parallel forward and rear faces 65 and 66, respectively, inclined at angles to conform the blocks to the arc of the segmental cutter 250, when assembled thereon in oriented relation with respect to each other. The blocks 53 may be assembled and oriented in the proper bit pattern on the face 54 of the cutter 25c, and may then be welded together and welded or otherwise secured to the advance face 54 of said cutter.

It may be seen from the foregoing that I have provided a simple and efficient bit mounting means for a rotary boring head of a continuous mining machine in which the bit mounting means may readily be arranged to fit different cutting radii of the individual annular cutters of the continuous mining machine, and in which the pattern of the bits may readily be selected to suit various cutting conditions.

It may further be seen that the bit mounting means of the invention is of a simple construction, that the open sockets may be inexpensively made and are closed by the rear face of the next preceding bit mounting means and that the bits in cooperation with the tapered rear Wall of the socket, may be secured in place by a blow on the outer end thereof, without the use of the usual set screws or other holding devices, and may readily be removed by the insertion of a pry bar in the opening 61 and exerting a prying force on the inner end of the bit.

While I have herein shown and described one form in which my invention may be embodied, it should be understood that various modifications and variations of the invention-may be effected without departing from the spirit and scope of the novel concepts of the invention as defined by the claims appended hereto.

I elaim as my invention:

1. In a mounting device for cutter bits and the like, a plurality of individual blocks adapted to be arranged in abutting relation with respect to each other, each block having an 'open bit receiving recess cut in an advance face thereof and having parallel side walls and a rear wall diverging outwardly from the inner side of said recess and conforming to a rectangular tapered shank of a cutter bit, an opening leading transversely through each block and intersecting said open recess adjacent the inner end thereof, and means securing said blocks in abutting engagement with respect to each other and closing the advance ends of said recesses.

'2. In a cutting device for coal and the like, a rotary cutter having an arcuate advance face, cutter bits adapted to be mounted on said advance face and project forwardly therefrom and having rectangular shanks, and bit mounting means for said cutter bits including a plurality of individual blocks adapted to be secured to said advance face, each'block having an open recess therein having two parallel walls and opening to a forward face thereof and having an apertured portion extending transversely thereof and intersecting said open recess, said blocks being ar ranged in abutting relation with respect to each other with the rear face of one block closing an open recess of the next adjacent block and said blocks being oriented to the desired bit pattern and arranged to conform to the face of said cutter, and means securing said blocks together in assembled relation with respect to each other.

3. In a cutting device for coal and the like, a rotatable cutter having an advance face, cutter bits for mounting on said advance face to project forwardly therefrom and having tapered shanks generally rectangular in cross sec- 4 tion, and bit mounting means for mounting said cutter bits on said advance face including a plurality of individual blocks adapted to be positioned on said advance face in abutting relation with respect to each other and having advance and rear faces, said blocks having bit receiving recesses formed therein opening to the advance faces thereof, each recess having parallel side walls and an inclined rear wall diverging outwardly from the inner side of said recess and conforming to the taper of a tapered shank of an associated bit, said mounting blocks also each having an open portion extending transversely thereof and intersecting said open recess at the inner end thereof, and

, said blocks being oriented on said cutter in abutting relation with respect to each other and welded thereto and to each other.

4. In a cutting device for coal and the like, a rotatable cutter having an elongated arcuate advance face, cutter bits for mounting on said face to project forwardly therefrom having rectangular shanks having tapered rear walls, and bit mounting means for mounting said cutter bits on said face including a plurality of individual blocks having non-parallel forward and rear faces positioning said blocks to conform to the arc of said cutter when in abutting engagement with each other, each block having an open recess therein opening to an advance face thereof and having an outwardly diverging rear wall diverging outwardly from the inner side of said recess and conforming to the taper of the tapered rear wall of an associated cutter bit, each of said blocks also having an open portion adjacent the inner end thereof intersecting said open recess to accommodate removal of a bit by a pry bar and the like, the rear face of an advance block closing an associated open recess and said blocks being adapted to be arranged in abutting engagement with each other on said cutter and to be mounted on said cutter and connected in abutting engagement with each other by welding.

References Cited in the file of this patent UNITED STATES PATENTS nhw I r- 

